Catless DP, Tune and P0420

[ZuMBLe]

It's pretty clear after 3 different tunes, there is nothing tuners can do about it.
Also, how is that the most important part of the stage 2 tune?
I would think the power increase is more important, it is for me.
It's not the end of the world, I'll just check my car with my AP once in a while to see if anything is going on.

At this point, from what I can see. The only way to guarantee losing the CEL is to go catted and not just that but pairing the tune you paid for with the downpipe said tuner also sells.
AKA. APR for example.

I've told my tuners about my CEL codes i'm getting related to my catless dp and they didn't really have anything to say about it, sounds like to me there is nothing they can do about it.
For now, the codes are harmless because it's just my car bitching about not having a CAT so whatever.

But yeah, a lot of people keep complaining about their ebay downpipes giving them CELs and their stage 2 tune not fixing it.
Many different downpipes and tunes and yet tons of people with CEL's unfixed.
Sounds like to me this is unavoidable for the most part.

Perhaps the mini-cat can fix it?
But a tune itself is very unlikely to fix it.
It almost seems like asking a tuner to remove a CEL is sort of like asking a tuner to remove the TD1 flag.

Tuners can turn off the CEL. If they do that, you have no chance at passing OBD emissions testing. Many tuners don't want to deal with possible EPA problems from messing with "emissions equipment".

Stage 2 = Aftermarket Downpipe
Aftermarket Downpipe = High flow cat or No Cat
High Flow Cat or No Cat = ECU seeing more fuel after the cat than it wants to.
More Fuel after cat than ECU wants to see = CEL

That's why a stage 2 tune has one job, to get rid of the CEL.

 

[bdelaney4000]

I honestly wish my tuner didn't patch the CEL mainly just because of the hassle of reflashing each year for emissions sake. I've asked and they don't offer a stage 2 tune without the CEL patch/readiness disabled. (Unitronic) Kind of wish I knew that before hand.

 

[ZuMBLe]

I honestly wish my tuner didn't patch the CEL mainly just because of the hassle of reflashing each year for emissions sake. I've asked and they don't offer a stage 2 tune without the CEL patch/readiness disabled. (Unitronic) Kind of wish I knew that before hand.

That's cuz the stage 2 tune has one job.....

Can you flash a stage 1 tune?

 

[bdelaney4000]

That's cuz the stage 2 tune has one job.....

Can you flash a stage 1 tune?

I can but Unitronic apparently also patches something on stage 1 too since readiness will not reset there either. I have no idea why they do that. So i unfortunately have to flash down to stock to pass emissions, it's like the most annoying 1-2 weeks of the year going from stage 2 to stock. I know its not just me either since some other Uni users on the forum have chimed in on these emissions conversations saying much of the same. I have contemplated going protune with a COBB access-port but I'd be starting from scratch again given the Uni-Connect Cable & Tune have zero resale value.

 

[ZuMBLe]

I can but Unitronic apparently also patches something on stage 1 too since readiness will not reset there either. I have no idea why they do that. So i unfortunately have to flash down to stock to pass emissions, it's like the most annoying 1-2 weeks of the year going from stage 2 to stock. I know its not just me either since some other Uni users on the forum have chimed in on these emissions conversations saying much of the same. I have contemplated going protune with a COBB access-port but I'd be starting from scratch again given the Uni-Connect Cable & Tune have zero resale value.

There must be some error! That's crazy that Unitronic would do that. Are you sure you don't just need to drive the car around a bit to get readiness with the stage 1? Unitronic can't be screwing over Stage 1 customers like that.

 

[bdelaney4000]

There must be some error! That's crazy that Unitronic would do that. Are you sure you don't just need to drive the car around a bit to get readiness with the stage 1? Unitronic can't be screwing over Stage 1 customers like that.

Yes definitely, I've become the drive cycle champion since being tuned. So much so that I got a copy of the VW GTI repair manual and have followed the drive cycle to the T. I even know that some the readiness sensors will not run if your fuel level isn't between 25-75%. Now I've got it down pat and can usually get the sensors reset in just a couple days of driving but it's annoying none the less. As far as why they do that who knows. I'm sure they also don't have to VIN lock their flash cables but they do.

 

[Desslok]

That's cuz the stage 2 tune has one job.....

I have the APR stage 2 tune, with the non-test pipe file. In other words, the O2 sensor works as intended. A spacer keeps the CEL from going off and all sensors are ready.

 

[ZuMBLe]

I have the APR stage 2 tune, with the non-test pipe file. In other words, the O2 sensor works as intended. A spacer keeps the CEL from going off and all sensors are ready.

If you can run the run the non-test pipe file, you can run the stage 1 file also. There is nothing you can't do with a DP that you can do with a DP. Nothing from a tuning standpoint anyway.

 

[sdmcoupe]

Tell them you want a new tune with a "test pipe" tune with the CEL turned off. Or use spacers to try to make the ECU happy.

GIAC wont provide that file. Its illegal for them to do so.

BTW, I'm catted. I'm still getting a CEL.

 

[ZuMBLe]

GIAC wont provide that file. Its illegal for them to do so.

BTW, I'm catted. I'm still getting a CEL.

Which DP do you have? A spacer can likely fix your issue.

 

[jimlloyd40]

I'm stage 2 with Catless downpipe, I've went through 3 different stage 2 tunes and I still get a CEL lol
I forgot the exact codes I get but yeah.

There is obviously a big misconception that a stage 2 tune will guarantee you will lose the CEL.

Not with the right tuner.

 

[ZuMBLe]

Not with the right tuner.

The problem could be legalities. The difference between a stage 1 tune and a stage 2 tune is literally 1-3 check boxes.

 

[draza74]

Not with the right tuner.

Well if Ed and Strat are not proper tuners, I don't know where else to go.

 

[jimlloyd40]

Well if Ed and Strat are not proper tuners, I don't know where else to go.

EQT and Stratified are both good tuners. Who tuned yours?

 

[draza74]

EQT and Stratified are both good tuners. Who tuned yours?

Ed tuned mine and Alex iirc from Strat did mine